The invention relates to an apparatus for aligning electrical components with two aligned connecting wires to form a belt, wherein two adhesive tapes respectively drawn from a delivery spool, secure the connecting wires between them, with two rotary drivable conveying gear wheels arranged on a shaft and receiving the connecting wires in tooth gaps, with two rollers arranged on the shaft, each guiding one of the adhesive tapes and with pressing means in each case pressing the second adhesive tape in congruent manner on the first adhesive tape whilst incorporating the connecting wires.
Apparatus for aligning electrical components with two aligned connecting wires or belting or binding means are described, for example, German Pat. No. 2,618,383 and DOS 2,813,100 the details of which are incorporated herein by reference. More particularly, with regards to constructional details of the overall machine, to the extent that corresponding developments are not described in the present application and particularly to the extent that not diverging developments are described herein. The known belting means have a casing with a drive and optionally a gear, by which the spacings of the components can be differently adjusted on the belt to be produced. A driven shaft projects out of the casing and on it are mounted the conveying gear wheels and rollers in a non-rotary manner. The tooth gaps of the conveying gear wheels receive the connecting wires and the components are held and conveyed in this manner. A first adhesive tape is placed around each of the rollers, with an adhesive surface thereof being directed towards the outside. After placing the components in the conveying gear wheels, part of the wires of the components rest on the adhesive surface of the adhesive tape. Then, for as long as the components are guided by the conveying gearwheels and the connecting wires rest on rollers, a further adhesive tape is guided over the areas of the connecting wires resting on the rollers and under the action of an elastic force, such as an elastically mounted pressing roll, is pressed against the connecting wires and the areas of the lower adhesive tape located between said wires. Optionally, as proposed in DOS 2,813,100 the connecting wires of the components are straightened before being placed in the conveying gear wheels. The completely belted components are then wound as a finished belt onto a draw-off roll.
The above proposed apparatus function in a largely satisfactory manner. However, the connecting wires of the components can have a different length, so that they project to a varying degree beyond the belts. It is also desired that the belted components have connecting wires of specific predetermined lengths. It would theoretically be possible to provide separate cutting means which deflect the connecting wires upstream or preferably downstream of the belt. However, this is complicated and experiments have shown that the belted components are not adequately secured between the belts, so that particularly when cutting is effected, displacement thereof occurs, or the connecting wires may slide out between the belts. Moreover, in the proposed belting machines, the pressing means is constructionally complex, which complicates the adjustment of the axial spacing.
Therefore, the aim underlying the present invention essentially resides in providing an apparatus of the aforementioned type in which constructionally simple means are provided for the actual belting operation, and which permits an easier adjustability and also a better support of the belted components between the adhesive tapes. According to the invention, each roller is associated with a compact working member, which has guidance and alignment means for the second adhesive tape, the pressing means and a cutting means for cutting off the connecting wires of the components.
The compact working member provided according to the invention and which, as stated above, includes means for performing several functions, but is of a simple construction and permits an easier adjustment. For example, in a known manner, following the release of an attachment for the working member, the latter can be adjusted at the same time as the rollers. The axial adjustment of the apparatus according to the invention takes place more simply than in the case of known apparatus. Moreover, through the construction of a cutting means in or on the working member, it is possible to achieve a deflection of the connecting wires to their desired length when the wires are in any case under a maximum pressure for belting purposes, so that there is no need for a subsequent cutting with the resulting problems with respect to the individual components having to be released from the belt. Due to the fact that the guidance means is constructed in the actual working member and, consequently, necessarily upstream of the roller and the pressing means or up to the latter, it has a relatively simple construction, so that complicated guidance means, as used in the prior art, are no longer necessary.
According to the present invention, the working member is constructed as a compact block having a guide groove for the second adhesive tape and a pressing roll mounted therein which is axially displacable relative thereto and radially overlapping the same, with the guide groove being aligned over the pressing roll, and with the pressing roll, resting on the roller and the cutting roll, being positioned directly adjacent the roller and radially overlapping the same, so that the circumferential edge of the roller cooperates as a cutting edge with the cutting roll. Due to the construction of a guide groove formed with the roller in the radial direction within the working member in the form of a compact block, there is no need for guidance means in the conveying direction and upstream of the guide groove, which precisely guide the adhesive tapes. In fact, unlike in the prior art, the adhesive tapes can be deflected or guided in a random manner, with considerable tolerances with respect to a lateral displacement of the running path of the adhesive tapes, with the path not being precisely prescribed. With the inventive construction of the guide groove in the working member, it would appear desirable, particularly if the adhesive tapes are guided on their conveying path from their delivery spool to the guide groove, to provide means over which the adhesive tapes are guided, on which the tapes can relatively freely move at right angles to their conveying direction, so that they largely automatically select their conveying path with respect to a lateral displacement and can consequently optimize the same. Thus, the invention permits a preferred construction in that adhesive tape guides are provided in the conveying direction upstream of the working member and/or the roller, with the adhesive tape guides being of a fixed width projecting by a multiple over the width of the adhesive tapes and with the tape guide including radially elastically outwardly pressed cutting edges. This construction makes it possible to eliminate electro optical limit switches with complicated electronics. The end of an adhesive tape or a fault through slackening of the exerted tension can be determined by the elastically mounted cutting edge, which is connected to a switch and, consequently, in the case of a fault, the apparatus according to the invention can be stopped, so that no serious damage occurs.
According to further features of the present invention, the circumferential edge of the cutting roll in the contact line of the pressing roll and roller intersects the circumferential cylinders thereof and in particular the tangent on the cutting roll extends vertically in the contact line to the tangential planes of roller and pressing roll. As a result, in the case of maximum pressure, the contact wires are cut off, with the edge of the roller acting as a second cutting edge associated with the cutting edge of the cutting roll. In accordance with advantageous features of the present invention, the cutting takes place in such a way that, through cutting the connection wires, no force is exerted in or counter to the feed direction, but merely at right angles thereto. This is particularly aided by the fact that the pressing roll is rotatable, but otherwise rigidly mounted and that in the circumference of the roller axially parallel grooves are formed, which are aligned with the tooth gaps of the conveying gear wheels. Due to the construction of grooves, the connecting wires, which are initially placed on the adhesive tapes stretched over the grooves, can be pressed with the first adhesive tapes into the grooves and, consequently, the first adhesive tapes wind around them in an optimum manner, which gives an optimum support together with the placed-over and pressed-down second adhesive tape. Both in areas of the belt in which connecting wires are arranged between both adhesive tapes, and on areas between the connecting wires where the adhesive tapes are directly stuck to one another, advantageously substantially the same contact pressure is exerted for producing the bond, so that, it is not possible that as a result of an adequate contact pressure, no reliable bond is achieved between the adhesive tapes, as in the prior art, because it is then necessary to allow the pressing members to elastically yield in accordance with the height of the components. The pressing rolls are preferably made from an elastic material and, in particular a hard elastic plastic material which, although able to absorb slight tolerances, is not so soft that it can be dented over long periods of time without a great force being exerted thereon. Moreover, by virtue of the present invention, there is no longer any need for an elastic mounting of the pressing rolls, so that the complete working member can be firmly pressed with the pressing roll against the roller during adjustment and can be secured or fixed in this position. The formation of grooves in the roller also makes it possible, in advantageous manner, to obtain a forced fixing of the spacing of the individual components and it is obviously possible to leave certain grooves free, instead of placing the components in each of the succeeding grooves. Adjustment may be accomplished by a stepping motor, with the step size and the presence of the components at the belting point being monitorable by light monitors, which, in particular, stop the belting process when there are no components, so that belting only takes place when there are components. This leads to a considerable advantage compared with mechanical gears, which continue to belt if no components are present.
The above and other features will become more apparent from the following description when taken in connection with the accompanying drawings.